Front Panel Audio connector

[The Great Kamek]

Coming from Paul's video, he says front connector's audio is not the best. Is it true? ATt 25:25 mark

 

[mariushm]

In general front panel audio connectors are not great, because the wires have to travel all the way from the bottom corner of the motherboard (typically) over the motherboard and go diagonally towards the top of the case... so it's a lot of distance where analogue signals travel through basically unshielded wires.

 

There's no coaxial cable like you have on headphones or speakers where the ground wire surrounds the signal wire, you have separate wires and noise from various components like the video card or other components on the motherboards can affect the sound quality.

 

In case you don't know what coaxial means here:

 

 

You see the red and white wires which carry the left and right speaker signals and the ground wire which is actually a mesh of copper strands that surround the two signal wires and behave like a shield, protecting the inside wires and blocking noise.

Cases use regular wires because of the HD Audio / AC97 header which make it a bit difficult :

 

 

 

The connectors on the back are a bit better because the audio signals typically travel through the circuit board to the connectors, and the connectors are on the outside of the computer case, and the case acts like a shield.

 

[rice guru]

33 minutes ago, The Great Kamek said:

Coming from Paul's video, he says front connector's audio is not the best. Is it true? ATt 25:25 mark

 

yes they are probably the worst option to use on your pc as they often have poor cables and poor shielding which are unacceptable to noise and overall just wont sound as good as your motherboard audio, if your on apc right now you can test it out yourself and see if you hear a difference I tried on mine and the difference was significant enough that I never plug anything through my front panel audio 

[The Great Kamek]

45 minutes ago, mariushm said:

In general front panel audio connectors are not great, because the wires have to travel all the way from the bottom corner of the motherboard (typically) over the motherboard and go diagonally towards the top of the case... so it's a lot of distance where analogue signals travel through basically unshielded wires.

 

There's no coaxial cable like you have on headphones or speakers where the ground wire surrounds the signal wire, you have separate wires and noise from various components like the video card or other components on the motherboards can affect the sound quality.

 

In case you don't know what coaxial means here:

 

 

You see the red and white wires which carry the left and right speaker signals and the ground wire which is actually a mesh of copper strands that surround the two signal wires and behave like a shield, protecting the inside wires and blocking noise.

Cases use regular wires because of the HD Audio / AC97 header which make it a bit difficult :

 

 

 

The connectors on the back are a bit better because the audio signals typically travel through the circuit board to the connectors, and the connectors are on the outside of the computer case, and the case acts like a shield.

 

I am unable to use the back since my Ethernet cable is blocking the space for the mic connector.

[mariushm]

32 minutes ago, The Great Kamek said:

I am unable to use the back since my Ethernet cable is blocking the space for the mic connector.

Most modern sound cards have auto configuration. Try plugging the microphone in line in jack - the software that comes with driver should pop up and ask what you plugged in or auto-detect microphone.

On other... you can select role from software... in my case, see picture below, i can double click the default microphone in icon on the right and select another role...same for the other jacks

 

 

[The Great Kamek]

11 hours ago, mariushm said:

Most modern sound cards have auto configuration. Try plugging the microphone in line in jack - the software that comes with driver should pop up and ask what you plugged in or auto-detect microphone.

On other... you can select role from software... in my case, see picture below, i can double click the default microphone in icon on the right and select another role...same for the other jacks

 

 

Oh I can make it switch function if I were to plug it in different connector?

[mariushm]

Yeah, try it out ... even if for some reason it doesn't work, it won't damage the microphone or motherboard.

 

Line In and Mic are both inputs, just different levels .. think of line in as a pre-amplified microphone, so if you plug mic in line in jack sound card will simply see it as very weak line in signal. It will either auto detect microphone or you can manually tell it it's microphone and then audio chip treats signal correctly or worst case scenario it won't work and you didn't lose anything...

 

A lot of audio chips are 5.1 or 7.1 capable but on cheaper motherboards you may have only 3 analogue connector (by default, stereo out, line in, mic)

So for 5.1, line in and mic jacks are reconfigured for center+subwoofer and rear/side left+right.

For 7.1, headphone jack on front panel becomes those extra 2 channels above 5.1

It can be used as line in on some audio chips when back line in is used as 5.1

 

So in order to allow this dynamic reconfiguration chips implement that auto-detection to figure out what you plugged in...or should let you specify manually.

[The Great Kamek]

1 hour ago, mariushm said:

Yeah, try it out ... even if for some reason it doesn't work, it won't damage the microphone or motherboard.

 

Line In and Mic are both inputs, just different levels .. think of line in as a pre-amplified microphone, so if you plug mic in line in jack sound card will simply see it as very weak line in signal. It will either auto detect microphone or you can manually tell it it's microphone and then audio chip treats signal correctly or worst case scenario it won't work and you didn't lose anything...

 

A lot of audio chips are 5.1 or 7.1 capable but on cheaper motherboards you may have only 3 analogue connector (by default, stereo out, line in, mic)

So for 5.1, line in and mic jacks are reconfigured for center+subwoofer and rear/side left+right.

For 7.1, headphone jack on front panel becomes those extra 2 channels above 5.1

It can be used as line in on some audio chips when back line in is used as 5.1

 

So in order to allow this dynamic reconfiguration chips implement that auto-detection to figure out what you plugged in...or should let you specify manually.

So I tried them out in the back, and I don't think I notice any differences.

[mariushm]

Of course, it would depend on the quality of your microphone, your sound card, how good your ears are...

 

Typically you'd hear a higher background noise, or some high pitch noise from time to time, or buzzing that would vary in intensity depending on what you play (for example when you transition from some high action scene to something more "static" like pressing escape to go in menu, reducing the video card's power consumption and then back)

I notice differences with a 40$ Sony lapel microphone but it would be hard to spot differences with a 2$ desk microphone.

 

[Spuriae]

Depends on the motherboard and how it's implemented. Often on midrange and mid-high-end boards the front headphone out will have additional external amplification. The Realtek integrated headphone amplifier, not the DAC, is the performance limiter; it doesn't matter much if the 16 or 24 bit DAC is used since distortion and noise will be dominated by the headphone amplifier... unless the output is configured as line out with an external amplifier, which happens more often with the front than the rear output. On most low-end boards there will be no functional difference between the front and rear outputs (the ALC892 doesn't reach 16 bit analog performance on any DAC/ADC).

 

As for microphones, while the rear mic tends to have more dynamic range, this appears to be purely based on the digital format. In all other respects the two ADC's on a Realtek codec perform identically, implying that physically the two are the same but one is limited to 16 bit signalling. There are no microphone amplifiers; all gain is in software. This is where the dynamic range limitation becomes relevant, as the 24 bit ADC has an extra ~10dB of functional noise floor. On most boards the front jack will only have the 16 bit option. If you don't use the software boost and don't need 24 bits of resolution (or are using a low-end board), then there's no functional difference between the two. Otherwise the rear input is usually better.

 

Concerns about noise are mostly overblown. Since the computer case is grounded, the signal is well-protected as long as it is routed along the surface of the case and not bundled with the other front panel cables. The only other significant noise source on the front panel is USB, but the only low frequency signal there is the 1kHz/8kHz frame rate, and the data conductors are differential. Besides, crosstalk is only a significant concern at high frequencies; both capacitive and inductive coupling are functions of the derivative of level changes. At audio frequencies, effects should be negligible.

 

Run two audio wires less than a millimeter apart inside the same cable and everyone's okay with that, but run an audio cable a couple inches away from a low-voltage noise source that doesn't even produce audio-frequency signals and everyone loses their minds. I don't get it.

[The Great Kamek]

6 hours ago, Nimrodor said:

Depends on the motherboard and how it's implemented. Often on midrange and mid-high-end boards the front headphone out will have additional external amplification. The Realtek integrated headphone amplifier, not the DAC, is the performance limiter; it doesn't matter much if the 16 or 24 bit DAC is used since distortion and noise will be dominated by the headphone amplifier... unless the output is configured as line out with an external amplifier, which happens more often with the front than the rear output. On most low-end boards there will be no functional difference between the front and rear outputs (the ALC892 doesn't reach 16 bit analog performance on any DAC/ADC).

 

As for microphones, while the rear mic tends to have more dynamic range, this appears to be purely based on the digital format. In all other respects the two ADC's on a Realtek codec perform identically, implying that physically the two are the same but one is limited to 16 bit signalling. There are no microphone amplifiers; all gain is in software. This is where the dynamic range limitation becomes relevant, as the 24 bit ADC has an extra ~10dB of functional noise floor. On most boards the front jack will only have the 16 bit option. If you don't use the software boost and don't need 24 bits of resolution (or are using a low-end board), then there's no functional difference between the two. Otherwise the rear input is usually better.

 

Concerns about noise are mostly overblown. Since the computer case is grounded, the signal is well-protected as long as it is routed along the surface of the case and not bundled with the other front panel cables. The only other significant noise source on the front panel is USB, but the only low frequency signal there is the 1kHz/8kHz frame rate, and the data conductors are differential. Besides, crosstalk is only a significant concern at high frequencies; both capacitive and inductive coupling are functions of the derivative of level changes. At audio frequencies, effects should be negligible.

 

Run two audio wires less than a millimeter apart inside the same cable and everyone's okay with that, but run an audio cable a couple inches away from a low-voltage noise source that doesn't even produce audio-frequency signals and everyone loses their minds. I don't get it.

 

 

 

 

 

my board is b350 Pc mate

[Spuriae]

3 hours ago, The Great Kamek said:

my board is b350 Pc mate

Doesn't matter for that board; there should be no difference between the front and rear with a standard ALC892 implementation.